The Bengaluru Development Authority has said the Hebbal tunnel road and rotary flyover project will not reduce Hebbal Lake’s area or obstruct its water flow, while promising monitoring measures during construction and completion by May 2028.
The short tunnel road is being built between Hebbal Junction and Mekhri Circle. According to BDA officials, the tunnel at Hebbal Junction will be constructed at least three metres below the lake bund. Engineers said the design would allow water to continue flowing into the lake without obstruction and that construction would not affect its water storage capacity.
The lake bund will be used for about a year during construction of the tunnel road. BDA officials said the work would then be carried out in a manner that remains compatible with the lake’s requirements. To record changes in water storage during construction, piezometers will be installed at the site. The readings will be displayed on locally installed boards and published on a website, the officials said during a media interaction.
The 2.2-kilometre tunnel will be constructed to prevent water seepage, according to BDA engineers. If water enters the tunnel despite those measures, 16 locally available five-horsepower pumps will be installed to remove it. Four additional pumps will be kept on standby, they said.
The project also involves tree removal and relocation. BDA officials said 56 trees would have to be removed for the tunnel and rotary flyover. As compensation, the authority plans to plant 560 saplings—10 for each tree removed—and maintain them for five years. A further 1,072 trees will be relocated to suitable locations and maintained, officials said.
BDA chairman N.A. Harris said the project was being implemented after inspections and on the basis of a report from senior experts at BMS College, along with advice from retired senior officials of the Central Ground Water Department. He said the authority was willing to consider technically sound suggestions from experts, including Professor Ashish Verma.
According to Harris, the tunnel road and rotary flyover are expected to benefit 40% of vehicles travelling between Hebbal Junction and Mekhri Circle. Vehicles arriving from Hebbal will be able to use the rotary flyover towards Yeshwanthpur and Jayamahal without stopping, he said. The road will be toll-free.
The project places a major traffic intervention alongside a lake and a substantial tree-protection programme. BDA’s stated safeguards will therefore depend on whether the water-level monitoring, pumping arrangements, tree relocation and replacement planting are carried out throughout the construction period. The authority has said the project is scheduled for completion by May 2028.
